/Engine/Source/Editor/UnrealEd/Classes/Editor/EditorEngine.h
Called before creating PIE instance(s).
virtual [FGameInstancePIEResult](API\Runtime\Engine\Engine\FGameInstancePIEResult) PreCreatePIEInstances ( const bool bAnyBlueprintErrors, const bool bStartInSpectatorMode, const float PIEStartTime, const bool bSupportsOnlinePIE, int32 & InNumOnlinePIEInstances )